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OTHER VEGETABLE FATS                         4I;

With chloroform and sulphuric acid it gives a reaction similar to that
of cholesterol (see General Methods, 19).

Its value depends essentially on the content of moisture and foreign
impurities and on the setting point of the fatty acids (titer). These, then,
are the principal determinations made (see General Methods, i, and also
Tallow) ; the acid saponificadon number is also measured and sometimes
the glycerine content (see General Methods).

* *

The titer of palm oil generally lies between 40 and 50. Its content of
water and foreign matters varies from 0-5% to 17%.but with a good specimen
should not exceed 2%. Commercial palm oil is always markedly acid ; when
recently prepared the oil may contain about 10% of free acids (calculated as
palmitic acid), but most commercial oils show 20-50%, while certain old oils
of special type may contain nearly 90%. As a rule the content of glycerine
diminishes as the free acid increases.

The best commercial oil is that from Lagos, with 2% of moisture and im-
purities at most; minimum titer, 43 ; acidity usually not greater than 20% ;
saponification number, 196-207. The Benin oil, which is brown, has the titer
40-49 and acidity up to 50%.


From the seeds of the oil-palm (Elaeis guineensis and E. melanococca],
It has the consistency of butter, is white or yellowish, has a special odour
similar to that of coco-nut oil and readily becomes rancid. In all its pro-
perties it closely resembles coco-nut oil (see Table XLV), from which it is
difficult to distinguish it. Analysis of this oil is carried out like that of

coco-nut oil (q.v.).


* *

In palm-kernel oil for industrial purposes up to i% of moisture and ex-
traneous impurities are allowed and up to 10 % of free acids ; saponification
number = 24.1-250 ; volatile acid number = 4-8-5-6 ; titer = 20-5-25-5.


Of the other vegetable fats the following are commonly known and used :

Vegetable Tallow or Chinese Tallow (Stillingia fat], from the seeds
of Stillingia sebifera. Its characters and properties may vary with the
method of extraction, but it is usually solid, hard and white outside and
more or less stained with earthy and vegetable residues, yellowish inside,
and odourless, or almost so.

Illipe"-nut Butter, Fat or Oil (Mahwa fat), from the seeds of Bassia
latifolia. It has a tallowy consistency, a yellowish or greenish colour and
a slight aromatic odour, and readily turns rancid.

Mowrah Butter, Fat or Oil, from the seeds of Bassia longifolia ; of
tallowy consistency, yellowish colour when fresh, rather bitter taste, and
odour recalling that of cacao seeds; it easily becomes rancid and decolorised.

The analysis of these, as of any other vegetable fat, comprises deter-
minations of moisture and foreign impurities, titer, acidity and saponifica-
A.C.                                                                                     27	>] ~ about i.